In August, several stations of the seismic network at San Salvador volcano recorded a few volcano-tectonic events 5 km from the crater. Local scientists investigated a fumarolic field, but nothing abnormal was found.

Information is preliminary and subject to change. All times are local (unless otherwise noted)

In August, several stations of the seismic network at San Salvador volcano recorded a few volcano-tectonic events 5 km from the crater. Local scientists investigated a fumarolic field, but nothing abnormal was found.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Cones

Feature Name

Feature Type

Elevation

Latitude

Longitude

14 de Marzo, Cerro

Pyroclastic cone

Aurora, Crater La

Tuff cone

Boquerón, El
Quezaltepeque

Stratovolcano

1893 m

13° 44' 3" N

89° 17' 38" W

Boqueroncito

Pyroclastic cone

1335 m

13° 44' 12" N

89° 17' 10" W

Cerrito, Cerro el
Balastrera, El Cerrito
Realenco, El

Pyroclastic cone

606 m

13° 48' 58" N

89° 15' 50" W

Ciega, Laguna

Pyroclastic cone

480 m

13° 50' 0" N

89° 21' 0" W

Grandes Bloques, Loma de

Pyroclastic cone

Hoya, Cerro la

Pyroclastic cone

Hoya, Plan de la

Tuff cone

Hoyo, Plan del

Pyroclastic cone

Jabalí, Cerro El
Amatepeque

Stratovolcano

1400 m

13° 45' 4" N

89° 19' 1" W

Joya, La

Pyroclastic cone

13° 42' 0" N

89° 16' 0" W

Laguna Caldera

Pyroclastic cone

505 m

13° 50' 26" N

89° 21' 24" W

Loma Caldera

Tuff ring

510 m

13° 51' 0" N

89° 22' 0" W

Picacho, El

Stratovolcano

1960 m

13° 44' 35" N

89° 25' 23" W

Playón, El

Pyroclastic cone

665 m

13° 48' 43" N

89° 19' 55" W

Resumidero

Tuff ring

Unnamed 1A

Pyroclastic cone

Unnamed 1B

Pyroclastic cone

Unnamed 2

Pyroclastic cone

Viboras, Montaña las

Pyroclastic cone

519 m

13° 50' 30" N

89° 20' 30" W

Craters

Feature Name

Feature Type

Elevation

Latitude

Longitude

Boca Tronadora

Fissure vent

480 m

13° 50' 0" N

89° 21' 0" W

Bogueroncitos

Fissure vent

13° 45' 0" N

89° 18' 0" W

Chanmico, Laguna de

Maar

466 m

13° 47' 0" N

89° 21' 0" W

Chinitos, Los

Fissure vent

500 m

13° 49' 0" N

89° 20' 0" W

Crater Lavas El Playón

Crater

Escondida, Crater la

Crater

Granadillas, Las

Maar

Jabali, Boca del

Crater

Jabalion

Crater

Puerta de la Laguna
Plan de la Laguna

Maar

800 m

13° 40' 0" N

89° 15' 0" W

Sitio Grande
Jabalincito, El

Crater

820 m

13° 46' 0" N

89° 20' 0" W

Basic Data

Volcano Number

Last Known Eruption

Elevation

LatitudeLongitude

343050

1917 CE

1893 m / 6211 ft

13.734°N
89.294°W

Volcano Types

Stratovolcano Caldera Pyroclastic cone(s) Maar(s)

Rock Types

MajorAndesite / Basaltic AndesiteBasalt / Picro-BasaltDacite

Tectonic Setting

Subduction zoneContinental crust (> 25 km)

Population

Within 5 kmWithin 10 kmWithin 30 kmWithin 100 km

29,514
800,780
2,857,563
6,366,833

Geological Summary

The massive compound San Salvador volcano dominates the landscape W of El Salvador's capital city of San Salvador. The dominantly andesitic Boquerón stratovolcano has grown within a 6-km-wide caldera whose rim is partially exposed at Picacho and Jabalí peaks, which themselves were formed by collapse of an older edifice about 40,000 years ago. The summit of Boquerón is truncated by a steep-walled crater 1.5 km wide and ~500 m deep that formed during a major eruption around 800 years ago. It contained a crater lake prior to an eruption during 1917 that formed a small cinder cone on the crater floor; a major N-flank lava flow also erupted in this year. Three fracture zones that extend beyond the base of the volcano have been the locus for numerous flank eruptions, including two that formed maars on the WNW and SE sides. Most of the four historical eruptions recorded since the 16th century have originated from flank vents, including two in the 17th century from the NW-flank cone of El Playón, during which explosions and a lava flow damaged inhabited areas.

This volcano is located within the Joya de Ceren Archaeological site, a UNESCO World Heritage property.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Deformation History

There is no Deformation History data available for San Salvador.

Emission History

There is no Emissions History data available for San Salvador.

Photo Gallery

This small andesitic cinder cone formed on the floor of the summit crater of the Boquerón cone at San Salvador volcano in 1917. The eruption began on June 6 from NW-trending fissures on the upper north flank of Boquerón. A chain of cinder cones formed, and a lava flow traveled to the northwest, cutting the railroad between Quezaltepeque and Sitio del Niño. The Boquerón summit crater lake began to boil by June 10 and disappeared by June 28, after which this small cone (Boqueroncito) formed on the crater floor.

Photo by Mike Carr, 1979 (Rutgers University).

The barren lava flow in the foreground was formed during a 1917 eruption from vents on the flank of Boquerón stratovolcano, the rounded peak at the left. The lava flow cut the railway SW of Quezaltepeque. The 1917 eruption also produced a small cinder cone in the summit crater of Boquerón. Boquerón has grown within a 6-km-wide caldera whose western rim forms El Jabalí peak (right). Three fracture zones that extend beyond the base of the volcano have been the locus for numerous flank eruptions of Santa Ana volcano.

Photo by Kristal Dorion, 1994 (U.S. Geological Survey).

Laminated pyroclastic-surge deposits at the right surround the walls of houses buried by an eruption from Laguna Caldera, a cinder cone on the lower NW flank of San Salvador volcano. This eruption was radiocarbon dated at about 590 CE and buried at least three Mayan homesteads beneath more than 4 m of scoria and ash. Archeological excavations near the hamlet of Cerén have revealed insights into Protoclassic Mayan life.

Photo by Giuseppina Kysar, 1999 (Smithsonian Institution).

Boquerón volcano, its summit cut by a steep-walled, 500-m-deep crater, was constructed within a 6-km-wide caldera whose largely obscured rims are visible in this aerial photo from the WSW. The caldera cut an older San Salvador edifice, remnants of which are visible at El Picacho peak (in the shadow behind Boquerón) and El Jabalí (the low peak at the lower left). The buried caldera rim in the foreground is defined by the change in degree of dissection of the volcano's flanks. Guazapa volcano can be seen in the distance at the top of the photo.

Oxidized reddish scoria deposits are exposed in a quarry on Cerro el Cerrito, a pyroclastic cone on the lower northern flank of San Salvador volcano. This cone (also known as Quezaltepeque, El Realenco, or El Cerrito Balestrera) is located immediately SE of the town of Quezaltepeque and is the NE-most of a chain of NE-SW-trending cones erupted along a fissure cutting across the northern flank of San Salvador volcano.

The 1.5-km-wide Boquerón crater (left) was formed during a major eruption about 1200 CE that truncated the summit of the post-caldera Boquerón stratovolcano. The 0.3-0.5 cu km San Andrés Talpetate Tuff produced during this eruption extended primarily to the west and was accompanied by pyroclastic flows. The eruption was named for the San Andrés archaeological site, where it was first identified. The outskirts of the city of San Salvador encroach on the volcano at the right.

A cable car line to San Jacinto on the SE side of the city of San Salvador provides access to this impressive vista of the massive compound volcano of the same name towering above the sprawling capital city of El Salvador. The flat-topped peak at the left is Boquerón stratovolcano, which has grown within a 6-km-wide caldera formed by collapse of the older El Picacho volcano (the peak at the right) and another volcano to the NW. Most of the four historical eruptions recorded at San Salvador since the 16th century have originated from flank vents.

Photo by Rick Wunderman, 1999 (Smithsonian Institution).

The dark-colored lava flow in the center of the photo originated during an eruption in 1917 from a vent high on the northern flank of Boquerón volcano (upper right). On June 6, 1917 an eruption began from NW-trending fissures on the upper north flank of Boquerón. A chain of cinder cones formed and a lava flow traveled to the northwest, cutting the railroad between Quezaltepeque and Sitio del Niño. Eruptive activity also occurred at the summit crater of Boquerón, where a small conelet formed on the crater floor. El Picacho peak is at the left.

Photo by Giuseppina Kysar, 1999 (Smithsonian Institution).

An excavation at the Joya de Cerén archaeological site near the hamlet of Cerén shows pyroclastic-surge deposits from the 590 CE eruption of Laguna Caldera lapping against Mayan buildings. The excavation has unearthed several small Protoclassic Mayan homesteads that were buried by this eruption from a cinder cone on the northern flank of San Salvador volcano. The eruption occurred suddenly, as seen from the remains of uneaten meals left by occupants who fled their houses.

Photo by Giuseppina Kysar, 1999 (Smithsonian Institution).

An archeological excavation near the hamlet of Cerén has unearthed several small Protoclassic Mayan homesteads that were buried by an eruption from nearby Laguna Caldera, a cinder cone on the northern flank of San Salvador volcano. The eruption occurred suddenly, as seen from the remains of uneaten meals left by occupants who fled their houses. The eruption was radiocarbon dated at about 590 CE.

Photo by Rick Wunderman, 1999 (Smithsonian Institution).

The massive Pleistocene Guazapa stratovolcano (left-center) is seen here in an aerial view from the SW with the Río Lempa behind it. The youngest flank vent of Guazapa is Cerro Macanze, which lies on the SE flank of the volcano, behind the two small volcanoes in the right-center part of the photo. The dark-colored unvegetated lava flow in the foreground was erupted in 1917 from the flank of San Salvador volcano.

Photo by Paul Kimberly, 1999 (Smithsonian Institution).

The SW corner of Ilopango caldera is visible in the foreground with the outskirts of the capital city of San Salvador in the middle distance. The high peak on the left horizon to the NW is El Picacho, part of the San Salvador volcanic complex, a historically active volcano overlooking the capital city. Below it to the left is San Jacinto, a Pliocene lava dome complex. The low peak on the upper right horizon is Cerro Nejapa, a Pliocene volcano in the Interior Valley of El Salvador.

Photo by Bill Rose, 1978 (Michigan Technological University).

The 8 x 11 km wide Ilopango caldera fills the center of the image in this view from the ESE. Fresh, light-colored exposures of the Tierra Blanca Joven formation in the foreground associated with the latest caldera-forming episode were in part created by landsliding during the January 2001 earthquake. The capital city of San Salvador lies beyond the lake, between it and San Salvador volcano (upper right). The Santa Ana volcanic complex lies beyond San Salvador volcano on the right horizon.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

El Playón cinder cone on the lower NW flank of Santa Ana volcano was formed during an eruption in 1658. An explosive and effusive eruption began immediately following a major earthquake on November 3, 1658 that destroyed San Salvador City and surrounding areas. Ash fell in Comayagua, and a lava flow (left horizon) traveled to the NE and surrounded the village of Nejapa. The dark-colored lava flow in the foreground originated in a 1917 eruption from a vent on the upper northern flank of San Salvador.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

Flat-topped Cerro Alto (right center), a 953-m-high cinder cone on the SE flank of Coatepeque caldera, is seen here from the southern rim of the caldera. Basaltic lava flows were erupted from the eastern side of the cinder cone. Cerro Alto predates formation of Coatepeque caldera and is blanketed by deposits from the caldera-forming eruptions. San Salvador volcano to the east forms the left horizon.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

The southern rim of Coatepeque caldera provides a dramatic view of the western side of San Salvador volcano. Flat-topped Boquerón volcano has grown within a large caldera cutting an older stratovolcano, of which rounded Picacho volcano to the left is a remnant. One of several cinder cones on the lower NW flank of San Salvador volcano is visible at the left-center margin. The flat, dark-brown colored area at the right center is the 1722 lava flow from San Marcelino cinder cone on the lower flank of Santa Ana volcano.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

The western slopes of San Salvador volcano rise above the Zapotitán basin beyond sugar cane fields south of Coatepeque caldera. The western flanks of the volcano and the rounded El Picacho peak left of the summit are part of the ancestral San Salvador volcano, which collapsed around 40,000-50,000 years ago to form a 6-km-wide caldera. Flat-topped Boquerón stratovolcano subsequently overtopped much of the caldera rim, and lava flows traveled down the northern and southern flanks of the ancestral volcano, smoothing its profile.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

The E-W-trending capital city of San Salvador extends across much of this Space Shuttle image (with north to the bottom) and encroaches on the flanks of San Salvador volcano. The steep-walled Boquerón crater is 1.5 km wide and lies within a late-Pleistocene caldera whose eastern wall is highlighted by the shadow left of Boquerón. The dark-colored area at the bottom right is a flank lava flow produced during the 1917 eruption of San Salvador volcano. The western tip of Lake Ilopango is visible at the left-center.

The false-color NASA ASTER image (with north to the top) looks down on the 1.5-km-wide summit crater of San Salvador volcano. The prominent dark-colored lava flow on the north side of the volcano was erupted from a flank vent in 1917. The tiny circular cone in the center of the summit crater was also erupted in 1917. The NW distal margin of the flow is cut by a highway. Lake-filled Laguna de Chanmico maar lies on the lower NW flank of the volcano at the left-center. The capital city of San Salvador is at the lower right.

GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Affiliated Sites

The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the MAGA Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO2 to the atmosphere, but installing CO2 monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

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